Locomotive exhaust apparatus.



D. R. MACBAIN. LOGOMOTIVE EXHAUST APPARATUS, APPLIOATION FILED MAYBI, 1912.

1,051,963. Patented Feb.4, 1913.

W I TNESSES gli s IVENTOR, QP I www@ @E mi Ml Todi 'ia/tem t mag/concern:

"""ED Smarts PATENT QFEIon "IOCasQsIv-r mamas' Be it knownthat I, R. M AAQBAIN, a citizen of'the United-States, residlng at Cleveland in the oeirnty of Cuyahoga and State of Ghio,. ha`ve 'invented certainnew and useful Improvements in Locomotlve 'Exhaust Apparatus, of which the following isa specification.

` My invention relatesA to locomotive `exhaust apparatus and particularlytothe exhaust nozzle of a locomotive.- It has for its primary obj ect Athe vprovision of animproved exhaust nozzle whereby increased draft is obtainedfand back pressure on .theJ cylinders reduced to a minimum, thus securing greater i efficiency in operation. This, together with such other objects as may hereinafter appear, or are incidental to my invention I attain by means of a construction illustrated in preferred form'in the accompanying drawings wherein,

Figure 1 is a transverse sect-ion throughthe front end of a locomotive diagrammatically showing the exhaust passages from t-he cylinders and the application of my invention;

Fig. 2 is a section on the line II-II of Fig'. 1; on the lines Figs. 3, 4 and 5 are sections taken III-III, IV-IV, and V-V, respectively, of Fig. vl; Fig. 6 is a lan vview of the top of the exhaust nozzle; ig. 1a and Fig. 2 are plan views of the exhaust stacks -of Fig. 1 and Fig. Q' respecexhausted from the stack during the opera` i of Fig. 1el

tively, diagrammatically showing the relative cross-sectional areas, density and locationof the volumes of steam and Agases tion of the locomotive; Fig. 7 is a transverse section of a locomotive front and diagrammatically illustrating the' arrangement ofparts usually employed in locomotive construction; Fig. 7-a isa view similar to those and Fig. i2a, but showsthe cornposition of the exhaust of the device of Fig. 7; Figs. S, 9 and`10 are sections taken on the lines VHF-VIII, IX-'IX and X--X, respectively, of Fig.,7 Fig. 11 is a plan view of the top of the exhaust nozzle shownin Fig. '7, and Fig. 8a is a section through the exhaust .nozzle on the line VIIIa-VIIIR l Referring to Fig. 7, it will be seen that I have diagrammatically illustrated in cross section the present general arrangement of the front end and exhaust passages of a locomotive. The shell'7 of the locomotive is mounted on the valve chest casting br saddle appunti@ inea my' 31, 1912. sealan-.roepen mounted the valves' I1 and-512 for controlling the admission. and exhaust of steam to and from the main cylinders. The exhaust steam is conducted to the exhaust nozzle 13 from the cylinders 9 and 10 by'theexhaust passages 14 and 15.; The cross section of the exhaust passages is rectangular (see Fig. 1 0) to conform to the shape of the exhaust ports. proximately rectangular in cross section and tapers to acircular section (see Figs. 8 and 8a) but the exhaust tip and the stack 17 are round, as will appear from an inspec" ftion of Figs. 7a Aand 11.

draft producedl `,by the exhaust depends The amount of largely upon the rate at which the steam is delivered from the exhaust tip to the stack, and it has been found that with the use of a round tip there is considerable resistance. encountered due to the changing of the exhaust steam from a rectangular to a circular section. This `not only retards the liow4 of steam from the exhaust nozzle with back pressure in the cylinders as a resulta-nt, but also causes thejet of'steam to spread rateteuFebA, 1913.

8 whichis 'withithe valve cylinders or chambersaS-Landl() in which are The'exhaust nozzle 13 is ap- L as it leaves the exhaust tip,I thus tending t0 completely 4fill the stack, thereby tionately decreasing t-he amount o from the lues which can be .entrained in the stack by the draft Aof the exhaust. A further result of the use of the round exhaust tip is that thesteam in the stack is most dense at the -sides which also serves to decrease the volume of entrained gases. The course of the exhaust steam is diagrammatiropor- Vcally indicated in Fig. 7 and as there shown,

.from the two cylinders follow each other with great rapidity. One of the chief objects of my invention isto provide a congases.

18 (see Fig. 7**)1 struction wherein the jet of exhaust steam is solidified and the spread thereof reduced, and the above enumerated defects avoided and greater eiiiciency of draft obtained. and back pressure in the cylinders reduced.

T accomplish the 'foregoing by providing :m exhaust tip which is of the same relative form ot cross section as the exhaust passages as will appear from an inspection of Figs. l to G. As there shown, the exhaust Vtip 1f) is rectangular in cross-section, sub stantiall)y corresponding' to the cross section ot the Mdiausi passages, as shown in Fig. 4. lt has been found that with the use of such a cziuislruution, the jet 21. of the exhaust steam is maintained in solidified forni due to the fact that the jet is not. changed in cross section just prior to discharge as in the case with round nozzles, and spreading thereof prevented, the 'steam being most dense 4at the central portion olf the jet, The power ofV the exhaust is thereby increased, inasmuch as the steam is discharged at a more rapid rate from the nozzle. ilt-has also been found that the jet is not carried as close to one side' of the stack, as previmisl)T pointed out, thus leaving a substantial area 2O in the stack extending entirely around the jet into which a larger volume of gases may be enlraincd, thus increasing the etlicienc'gT ol the draft. it.. will also be seen that with a boil;T of steam having a relatively rectangular sot-lion, there a more effective space for the entrainluent ot air between such body and the circular interior of the stack than `the case Where the cross-sectionalI area oli the steam circular. As a result, a better draft is secured with the nozzle having a rectangular outlet than is the case Where the noz- .zle has a circular outlet. By reason of the more effective cntraininent of air in the stack by reason of the long axis of the nozzle being placed longitudinally of the locomotive, the sectional area of the rectangular nozzle may be niade greater than is the case with a circular nozzle which is advantageous .in that this enlargement of the nozzle reduces the back pressure in tho cylinders. The construction therefore not only mate rially increases the draft in a locomotive, which is the prime object of the improvement, but also reduces the back pressure in the cylinders, giving the locomotive aarelatively higher ellioiency. Other advantages incident to the construct-ion will bi apparent lo those skilled in the art.

Having thus described my invention and illustrated 'its use7 what. l claiin as new and desire to secure by Letters Patent is the following:

l. lin a locomotive, the eoinbinationl with a stack, of exhaust nozzle with a tapc'iring interior surface and having the outlet open ing at its eXtreme end of a Cross seetion longer in one direction than inn thel other, with its lone' axis extending longitudinally of the locomotive, the said interior surtaee of the nozzle being throughout substantiall)Y smooth and unobstructed.

2. ln a' locomotive, the combination with a stach: Otan exhaust nozzle with a tapering interior surface and having the outlet` opening at its extreme end of a substantially rectangular Cross section, with the long axis thereoir extending longitudinally of the locomotive, the said interior surtaee of the nozzle being` throughout substantially smooth and unobstructed.

ilu testimony whereof I have hereunto signed my naine in the presence of the two subscribed witnesses.

Witnesses: Y

YW. l?. loninunoan RALPH ii'iolx'rosri,

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Eatents, Washington, D. 

